I blew my headgasket on my 1.5 EDM on a 0.5bar. The car was overheating and I just closed the boost and drove wery slowly while my new headgasket was being made. I made it 0.5mm thicker and it was from some material that is not metal but it is wery strong and it resist fire and high temp. ALSO i made shure that the gasket has reinforced inox rings over the cylinders. I told the guy that makes the gaskets that I am making 500hp turbo car and I nead the strongest material he has. He made it and it is great, car runs great and gasket costed me les that original.
Go and make custom headgasket.